听神经病谱系障碍患者噪声下言语识别能力研究

目的分析听神经病谱系障碍(Auditory neuropathy spectrum disorder,ANSD)患者噪声下言语识别能力。方法利用普通话版噪声下听力测试(Mandarin Hearing In Noise Test,MHINT),分别测试30例ANSD患者,16例感音神经性听力损失(sensorineural hearing loss,SNHL)患者和12例听力正常者在安静情况下和信噪比分别为15,10,5,0 d B的噪声条件下的言语识别能力。结果 ANSD组在噪声条件下的言语识别率显著低于SNHL组和听力正常组(P<0.05);ANSD组在安静条件下与信噪比为15 d B条件下的言语识别率差异无统计学意义(P>0.05),然而与信噪比为10、5和0d B条件下言语识别率差异均具有统计学意义(P<0.05)。安静情况下及噪声条件下,SNHL组和ANSD组言语识别能力与其听力损失程度均呈显著负相关(P<0.01)。结论 ANSD患者的言语识别能力较SNHL患者显著降低,大多数ANSD患者安静条件下言语识别尚可,但噪声情况下言语识别能力显著下降;噪声条件下言语测试对ANSD的诊断具有潜在的重要作用。     

可接受噪声级测试在助听器选配和人工耳蜗植入中的应用

在临床助听器选配中,许多助听器佩带者常抱怨噪声下言语理解困难,从而拒绝使用助听器,或将助听器搁置不用[1];而噪声下言语测试结果常不能准确地预估患者助听器使用成功与否。噪声下言语测试得分高者,其助听器使用并非成功[2]。个体背景噪声下的言语理解情况受很多因素的影响,如对背景噪声的感觉、喜好和习惯等[3]。为了更好地理解背景噪声对听力损失患者言语理解的影响,从而预估听     

噪声下言语识别能力评估

噪声下的言语理解和交流能力对日常生活中人与人之间的交流非常重要，听觉感知和言语识别是噪声下言语理解的基础。听觉感知是一个复杂的过程，需要积累足够的知识和言语处理技能，而言语识别是听觉感知中获取信息必不可少的组成部分。由于实际聆听环境存在各种噪声，因而噪声环境下的言语识别能力评估能够更真实客观地反映实际聆听效果。多年来，噪声下言语识别能力研究一直受到相关学者的广泛关注，二十世纪初问世的第一张英文辅音测听词表是用于电话通道质量测评，后来Fletcher等在贝尔实验室录制听力测试材料的目的是测试电话线路清晰度。随着听力诊断干预技术的蓬勃发展，噪声下言语识别能力评估逐渐被用于测试听力损失患者在日常生活中的交流困难程度，同时也能够用于快速有效地预测和评估助听装置在噪声下的言语提取分析能力［1，2］。虽然噪声下言语测试起步相对较晚，影响因素众多，具有很大的挑战性，但其在临床应用中的价值不可忽视。本文将重点阐述噪声下言语识别能力评估在临床工作和科学研究中的重要意义，对其众多复杂的影响因素进行分类探讨，概述国内外成人和儿童噪声下言语识别测试的发展。     

人工耳蜗植入儿童噪声下言语识别的研究

评估人工耳蜗植入效果的重要手段之一就是评价人工耳蜗植入儿童的言语识别率,但是,纯音听阈测试或安静环境下患者的言语识别能力并不能代表其日常生活(即噪声环境下)中言语识别能力,所以只有噪声下的言语测试才能更可靠地预测和评估人工耳蜗的实际应用效果.     

噪声下言语测听材料的发展历程

噪声下言语测听能较好地模拟日常交流的言语环境,且在评估受试者听力言语能力、指导听力障碍人士听力康复等方面发挥着不可替代的作用。随着噪声下言语测听在临床中的应用,临床迫切需要大量相关等价的言语测听材料以促进临床听力学的发展。本文主要阐述了国内外噪声下言语测听的发展现状、临床应用及相关测听材料的编制,为我国噪声下言语测听材料的开发提供帮助。     

感音神经性听力损失患者不同噪声模式下的言语识别能力研究

目的　研究不同噪声模式对听力正常者和感音神经性听力损失者言语识别能力的影响。方法　通过MATLAB软件播放儿童版汉语普通话噪声下言语测试句表,测试25名听力正常受试者和20例感音神经性聋受试者分别在安静环境、语谱噪声、双人语噪声下的言语识别能力,分析两者在安静和两种噪声模式下对语句感知能力的差异。结果　随信噪比降低,听力正常者在语谱噪声下言语识别率低于双人语噪声,但差异无统计学意义（P＞0.05）。感音神经性听力损失者在信噪比+5 dB时,双人语噪声下言语识别率低于语谱噪声,且差异有统计学意义（P＜0.05）。结论 　两种噪声模式对比,听力正常者在双人语噪声下言语识别率更高,感音神经性听力损失者在语谱噪声下言语识别率更高。     

正常人汉语噪声竞争下言语测听的临床研究

选用自行录制的单音节语音材料，对４６名听力正常青年人在３种不同噪声竞争下进行言语测听。选用的噪声为白噪声（ｗｈｉｔｅｎｏｉｓｅ，ＷＮ）、言语噪声（ｓｐｅｅｃｈｎｏｉｓｅ，ＳＮ）和自行录制合成的多人谈话声（Ｂａｂｂｌｅｎｏｉｓｅ，ＢＮ）。将测得言语识别率结果用两个参数的数学模型来表达信噪比（ｓｉｇｎａｌ－ｔｏ－ｎｏｉｓｅｒａｔｉｏ，Ｓ／Ｎ）与识别率间的关系。对正常人同时测试了安静条件下５个言语声级和３种噪声条件下５个Ｓ／Ｎ时的言语识别率。安静条件下测得的结果与沈晔结果相近，平均言语接受阈只相差１．８ｄＢ。噪声条件下言语识别率皆随Ｓ／Ｎ的变化而变化，同一噪声下，Ｓ／Ｎ越小识别率越低，Ｓ／Ｎ越大识别率越高。不同噪声下，５０％识别率水平时的Ｓ／Ｎ有明显差别，Ｓ／Ｎ在ＢＮ下最大，在ＷＮ下最小，说明不同噪声对言语识别的影响不同。噪声下测得言语清晰度曲线斜率比安静条件下要陡，不同噪声间清晰度曲线斜率无明显差别。本研究同时证实言语识别率的标准差与识别率水平和测试词表中词的数目相关。     

听力图正常者的信噪比损失现象

目的探讨听力图正常者是否存在信噪比损失（signal-to -noise ratio loss ，SNR loss）现象。方法对2010年3月至2011年4月在四川大学华西医院听力及耳科门诊就诊，主诉为生活环境中聆听言语较困难，但纯音测听、声导抗和常规言语分辨率（word recognition score ，WRS）测试结果正常的10名患者进行普通话版噪声下言语测听（Mandarin hearing in noise test ，M -HINT），并将结果与现有文献报道的M -HINT正常值进行比较（以结果高于正常值判断为出现了SNR loss现象），评估患者是否存在SNR loss现象。结果在噪声环境中，当噪声来自患者正前方时，10名患者均出现了SNR loss现象；当噪声来自患者右侧或左侧时，9名患者出现了SNR loss现象。结论听力图正常者也可能存在SNR loss现象，对于主诉为生活环境中聆听言语困难者，即使纯音听力图正常也应考虑进行噪声下言语测听（如M -HINT测试），以评估患者是否存在SNR loss现象。     

传导性聋患者在不同噪声竞争下的言语测听

目的　为了观察传导性聋患者在噪声竞争下言语清晰度曲线及不同噪声对清晰度曲线的不同影响;方法　测试２２ 名（３５ 耳） 传导性聋患者三种不同噪声竞争下测得的言语识别率结果,这三种噪声为①白噪声（ｗｈｉｔｅ ｎｏｉｓｅ,ＷＮ） ,②言语噪声（ｓｐｅｅｃｈ ｎｏｉｓｅ,ＳＮ） ,③多人谈话声（ｂａｂｂｌｅ ｎｏｉｓｅ,ＢＮ） ,即由８ ～１２ 人同时讲话录制而成,其频谱与言语长时平均频谱接近。所选用的测试词表为沈晔等有１９８３ 年编制的单音节语音平衡词表,每词表有２５ 个测试字。同时也测得不同信噪比（ｓｉｇｎａｌ ｔｏ ｎｏｉｓｅ ｒａｔｉｏ,ＳＮＲ）对清晰度曲线的影响。结果　传导性聋患者的言语识别率整体趋势是随ＳＮＲ 的增大而增加;不同噪声条件下清晰度曲线斜率变化不同,为ＢＮ＞ ＳＮ＞ ＷＮ,但无统计学意义;在信噪比较低时,ＢＮ 组的影响明显高于ＳＮ、ＷＮ 组（ Ｐ＜ ０ ．０５） 。结论　在嘈杂环境中,多人谈话声对言语识别的影响更明显     

Waardenburg综合征患者人工耳蜗植入术后听觉言语康复效果分析

目的评价Waardenburg综合征（Waardenburgsyndrome,ws）患者人工耳蜗植入术后的听觉言语康复效果。方法用纯音听阈、听觉行为分级标准（CategoriesofAuditoryPerformance,CAP）、言语可懂度分级标准（SpeechIntelligibilityRating,SIR）、儿童听觉言语能力家长评估问卷（Parents’EvaluationofAuraI／OralPerformanceofChildren,PEACH）,对行人工耳蜗植入术的4例WS1型患者、17例ws2型患者进行术后效果调查,并与非综合征且无明显病因的人工耳蜗植入患者比较,用SPSS13．0进行统计学分析。结果9例WS患者与9例对照组患者术后平均助听听阀（250Hz、500Hz、1000Hz、2000Hz、4000Hz）比较,差别无统计学意义（P〉0．05）。WS患者组CAP评分、SIR评分、安静环境下得分比、噪声环境下得分比、电话交流得分与对照组相比,差异均无统计学意义（P〉0．05）;WSl型组患者CAP评分、SIR评分、安静环境下得分比、噪声环境下得分比、电话交流得分与WS2型组患者相比,差异均无统计学意义（P〉0．05）,所有患者安静环境下得分比明显高于噪声环境下得分比（P〈O．05）。结论伴有重度或极重度感音神经性聋的Waardenburg综合征患者人工耳蜗植入术后的听觉言语能力与耳蜗形态正常的重度或极重度感音神经性聋患者无显著差别,安静环境下听觉言语能力好于噪声环境下听觉言语能力,且WS1型与WS2型患者人工耳蜗植入术后的听觉言语能力无显著差别。     

One‐stop neck lump clinic: phase 2 of audit. How are we doing?

One‐stop neck lump clinic: phase 2 of audit. How are we doing? Regular monitoring and audit of a service are integral to ensuring maintenance of efficiency and standards. This is particularly important where the quality of the service is operator dependent, as is the case in the clinical diagnosis of neck lumps and fine needle aspiration cytology. The one‐stop neck lump clinic has now been running in the department for more than 20 months. A previous article described the results of the first phase audit carried out at 6 months and had identified a waiting time to be seen that was longer than that recommended by the British Association of Otorhinolaryngologists, Head and Neck Surgeons. Measures were implemented to reduce this waiting time and a second audit was carried out after another 10 months with the aims of assessing if modification of the means of referral reduces waiting time and if the outcomes of clinical performance in phase 1 could be maintained or improved. We discuss the results of phase 2 in the audit spiral.     

A Decrease in Maxillary Sinus Pressure,as Seen in Upper Airway Allergy or Infection,Results in an Increase in Upper Airway Nitric Oxide Levels

The paranasal sinuses are connected to the nasal cavity via small osties. Ostial occlusion, caused by mucosal swelling, will result in a slowly increasing negative pressure inside the sinus cavity. In parallel, the oxygen content in the sinus will decrease, resulting in the development of relative hypoxia. Hypoxia is a powerful inducer of nitric oxide (NO) synthase, and inducible NO synthase has been shown to be present in considerable amounts in the upper airways, including the sinuses. The present study was designed to investigate whether a reduction in sinus pressure would affect upper airway NO production. Thirteen healthy volunteers were investigated. A pressure chamber was used to lower the ambient pressure to-4.9 kPa. NO was sampled from one nostril or via a drainage tube inserted into the maxillary sinus before, during and after the hypobaric exposure. When the pressure was decreased, NO levels increased from 256 &#45 15 to 316 &#45 19 ppb ( n =13, p <0.001). The NO levels remained elevated (282 &#45 21 ppb; p <0.05) when measurements were repeated 20 min after leaving the chamber. The nasal airway resistance (V2 tot ) also increased as a result of the chamber session (from 16 &#45 2° before to 21 &#45 3° after; p <0.05). An increase in NO levels was also found when the experiments were repeated with NO sampled directly from the maxillary sinus (225 &#45 6 before and 265 &#45 9 ppb after; n =6, p <0.001). For control purposes the nasal analyses were repeated again, this time under hyperbaric conditions (+4.9 kPa). This resulted in a slight decrease in the NO levels (from 273 &#45 22 to 241 &#45 17 ppb; n =10, p <0.001), but there was no change in the nasal airway resistance. We conclude that a reduction in sinus pressure, as seen in upper airway allergy or infection, may result in an increase in upper airway NO production.     

Physiologische Grundlagen einer Hörprothese

Zusammenfassung Im Bemühen, eine Hörprothese zu entwickeln, die ein Sprachverständnis erlaubt, erscheint es zumindest fürs erste am zweckmäßigsten, durch künstliche elektrische Reizung des Hörnerven die natürlichen Verhältnissen so gut als möglich zu imitieren. Der normale Hörnerv enthält etwa 30000 Nervenfasern, die sich qualitativ gleich, quantitativ jedoch unterschiedlich verhalten, wobei über die Eigenschaften der von den ÄHZ kommenden Spiralfasern im Augenblick sichere Aussagen nicht möglich sind (siehe 2.3). Die quantitativen Unterschiede zwischen den einzelnen Hörnervenfasern beziehen sich auf deren Frequenzabstimmung, Frequenzselektivität, Schwellen, Intensitätsfunktionen und — wichtig insbesondere für das Vorhaben einer künstlichen elektrischen Reizung — in Zeitunterschieden in den Aktivitätsmustern, die durch Laufzeitunterschiede auf der Basilarmembran bedingt sind (2.3). Diese Zeitunterschiede in der Aktivität einzelner Fasern liegen im Bereich mehrerer ms (2.3.6; 2.3.7). Die durch Schallreize im normalen Hörnerven ausgelösten Aktionspotentiale haben überdies einen probabilistischen Charakter, d. h. ihr Auftreten ist keineswegs streng determiniert. Es versteht sich von selbst, daß man bei künstlicher, elektrischer Reizung nicht alle verbliebenen Nervenfasern selektiv reizen kann. Somit wird eine Reizelektrode immer eine Gruppe von Nervenfasern erregen müssen. Bei jeder denkbaren elektrischen Reizung wären alle Fasern im Reizbereich einer Elektrode synchron und streng deterministisch aktiviert, was einen außerordentlich ernstzunehmenden Unterschied zu natürlichen Verhältnissen darstellt (3.2).Um die Zahl der zum Sprachverständnis mindestens notwendigen Reizkanäle abzuschätzen, wird man, in Ermangelung anderer experimenteller Daten, von psychoakustischen Untersuchungen an Normalhörenden auszugehen haben. Diese haben gezeigt, daß das Gehör neben einer außerordentlichen Fähigkeit verschiedene Tonhöhen zu unterscheiden, andererseits die Fähigkeit besitzt, bestimmte Frequenzgebiete zu sogenannten Frequenzgruppen zu integrieren. Die in eine solche Frequenzgruppe fallende Schallenergie wird zu einem einheitlichen Höreindruck verarbeitet. Es scheint also sinnvoll, die für einen Prothesenbau notwendige Zusammenfassung von Gruppen von Fasern des Hörnerven in verschiedene Reizkanäle entsprechend diesen Frequenzgruppen vorzunehmen (3.1). Demnach müßte der Sprachbereich in 15 Reizkanäle aufgeteilt werden, was wiederum, wenn man in der Cochlea reizen will, 1,2 mm Abstand von Kanal zu Kanal erlauben würde. Dabei müßte der Reizerfolg sauber auf die einzelnen Kanäle beschränkt bleiben, d.h. eine optimale Kanaltrennung erreicht werden. In Anbetracht der groben Abweichungen der neuronalen Aktivität vom normalen Verhalten, die bei künstlicher, elektrischer Reizung unvermeidlich sind, ist freilich unsicher, ob die angegebene Zahl ausreichen würde. Andererseits ist es in Anbetracht der zu erwartenden Stromverteilung im Sprachbereich kaum vorstellbar, mehr als die angegebene Zahl von Kanälen realisieren zu können.Was die Kodierung der Schallparameter innerhalb eines Elektrodenkanals betrifft, wird vorgeschlagen, die Frequenzkodierung nach dem Ortsprinzip optimal auszunutzen, und im Hinblick auf die Periodizitätsanalyse und die Lautheitskodierung sich soweit als möglich den natürlichen Verhältnissen anzunähern (3.3). Dabei wären Laufzeitunterschiede zwischen den Kanälen und der probabilistische Charakter der neuronalen Entladungen soweit als möglich einzuführen, um die Dominanz eines periodicity pitch zu vermeiden.Eine für Sprachverständnis ausreichende Prothese ist auch nur denkbar, wenn eine Prothese die zur Sprachübertragung notwendige Übertragungskapazität besitzt. Ergebnisse der Kanal-Vocoder-Technik zeigen, daß Sprache noch mit 1500 bit/s befriedigend übertragen werden kann. Eine Abschätzung der möglichen Leistungsfähigkeit einer 15-kanaligen Prothese (3.4), basierend auf der Zahl der möglichen unterscheidbaren Unterschiedsstufen der Hörempfindung, ergibt, daß diese Übertragungskapazität knapp erreicht werden könnte. Allerdings ist damit noch nicht gesagt, daß das Zentralnervensystem die angebotene Information auch im Sinne einer Phonemanalyse auswertet und damit für ein Sprachverständnis maximal ausschöpft. Nur für diesen Fall wäre ein Sprachverständnis zu erwarten.Als Reizort erscheint in erster Linie die Cochlea (5.1) geeignet. Für den Fall einer Degeneration der primären afferenten Fasern des Hörnerven ist aufgrund physiologischer Überlegungen auch der Nucleus cochlearis ventralis (5.5) interessant, allerdings würde so nur der ventrale Anteil der Hörbahn stimuliert. Doch besitzen auch andere Reizorte spezifische Vorteile (5.2–5.4).Theoretische Überlegungen (6.1) und experimentelle Messungen an implantierten Elektrodensätzen (6.3) zeigen, daß die Forderung der Kanaltrennung nur schwer zu erreichen sein wird. Deswegen wird der dynamische Bereich (im Hinblick auf Veränderung des Reizstromes) eines nach den obigen Kriterien konstruierten Reizkanals auf maximal 3 dB zu beschränken sein, so daß Erregungsausbreitung auf weitere Bereiche der Cochlea durch Ansteuerung von mehreren Reizkanälen zu imitieren wäre.Die Chancen, eine Prothese zu verwirklichen, die befriedigendes Sprachverständnis auf der Basis einer quasinatürlichen Reizung des Hörnerven erlaubt, wird von uns in Anbetracht der geschilderten mannigfaltigen Schwierigkeiten als sehr niedrig angesehen. In Anbetracht des großen Nutzens, der andererseits eventuell resultieren könnte, halten wir die Erforschung des Problems jedoch für angebracht.Es wird von uns vorgeschlagen, auch zu untersuchen, ob sich für eine prothetische Versorgung vorverarbeitete Sprache besser eignet (7.). Für Prothesen, die ein Sprachverständnis nicht anstreben, halten wir eine Implantation in die Cochlea für überflüssig. Hier erscheint uns die Implantation von Reizelektroden am runden Fenster (Douek et al., 1977; Fourcin et al., 1978; s. a. 1. und 7.) wegen des geringeren Risikos der überlegenere Weg.Die zitierten eigenen Arbeiten der Autoren wurden mit Unterstützung der DFG durchgeführt (DFG-K1 219).     

The expression of vascular endothelial growth factor (VEGF) and VEGF‐C in early laryngeal cancer: relationship with radioresistance

The expression of vascular endothelial growth factor (VEGF) and VEGF‐C in early laryngeal cancer: relationship with radioresistance Angiogenesis is essential for tumour growth and invasion. Vascular endothelial growth factor (VEGF) is a prime mediator of tumour angiogenesis. VEGF‐C is a closely related protein that effects lymphatic endothelial cells and may be important in the process of lymphatic metastasis. The purpose of this study was to evaluate the expression of these cytokines in patients with T1 and T2a glottic, squamous cell carcinoma, in comparison with normal epithelial control tissue, to ascertain any association with radioresistance. Twenty‐two tumours treated by radiotherapy (13 radiosensitive, nine radioresistant) and seven normal control tissues were studied. The minimum follow‐up was 2 years after radiotherapy. Expression of VEGF and VEGF‐C was evaluated by immunohistochemistry of formalin‐fixed, paraffin‐embedded biopsy specimens. Analysis was carried out using a quantitative computer image analyser. Both VEGF and VEGF‐C were detectable in tumour and normal control specimens. There was increased expression in tumour specimens of both VEGF (P = 0.03) and VEGF‐C (P < 0.001). In addition, the expression of VEGF‐C was associated with tumours of higher histological grade (P = 0.021). There was, however, no difference in VEGF and VEGF‐C expression between radioresistant and radiosensitive tumours. The expression of VEGF and VEGF‐C is increased in early laryngeal squamous cell carcinoma (SCC). However, measuring the expression of these proteins cannot predict radioresistance in this tumour group.     

Limited Surgery for Cancer of the Larynx and Hypopharynx: Options and Consequences

We reviewed surgical options for laryngeal preservation (limited surgery) in laryngeal and hypopharyngeal cancers and the consequences of the options. Of 44 patients with laryngeal cancer, 11 (25%) received limited surgery and 33 (75%) received total laryngectomy. The survival rates were 91% for the limited surgery group and 73% for the total (radical) surgery group. Of 31 patients with hypopharyngeal cancer, 7 (23%) received limited surgery and 24 (77%) received total laryngopharyngectomy. The survival rates were 53% for the limited surgery group and 40% for the total (radical) surgery group. The survival rates associated with limited surgery were thus better than those for total (radical) surgery for cancers of both the larynx and hypopharynx. This was attributed to the limited surgery group comprising well-selected patients with confined lesions. Organ preservation surgery should be technically simple, reliable in terms of its functional impact and, above all, should not jeopardize the patient's survival. Supracricoid subtotal laryngectomy with cricohyoidoepiglottopexy or cricohyoido-pexy has great potential for laryngeal preservation and will become the major limited surgery modality for treating cancer of the larynx. Limited surgery, however, needs to be performed with great care and is indicated only for very well-selected patients with cancer of the hypopharynx.     

Treatment of Maxillary Sinus Carcinoma: Clinical Results Using the Kitasato Modality

The conventional therapeutic regimen for maxillary sinus carcinoma consists of dissection of the maxilla, full-dose irradiation and extensive chemotherapy. However, the results obtained with this treatment are often poor. Even when patients recover, their quality of life is significantly reduced as a result of deformity of facial structures and swallowing and articulation dysfunctions. A retrospective analysis of 68 patients with maxillary sinus carcinoma treated with the Kitasato modality between 1975 and 1999 was conducted. All patients underwent pergingival maxillary sinus surgery combined with pre- and postoperative irradiation therapy with standardized total doses of 16 Gy; the postoperative irradiation was given in combination with regional intra-arterial infusion chemotherapy administered via the superficial temporal artery. All visible tumor lesions were removed where possible in order to preserve or facilitate cellular immunity after surgery. The cumulative 5-year survival rates were 85.7% for Stage II patients, 88.1% for Stage III, 76.6% for Stage IVA and 75.0% for Stage IVB.     

Cervical Reflex Induced by Click Stimuli in Cats

We studied click-evoked potentials in the anterior horn of the spinal cord in 17 cats. A concentric needle electrode was inserted into the anterior horn of the spinal cord at levels C3-C6. Potentials evoked with 105 dB SPL clicks were recorded with a peak latency of 4.89-5.10 ms only at the C3 level. These responses were observed 45-60 dB SPL above the auditory brainstem response (ABR) threshold, and no potentials were evoked by stimulation of the contralateral ear. Average was performed 100 times with changes in stimulation frequency of 1-20 Hz. The amplitude of the potentials decreased with increasing stimulus frequency, but there were no changes in ABRs. The responses disappeared after destruction of the medial vestibulospinal tract at the obex level, but ABRs were still recorded. The spinal nucleus of the accessory nerves was located in the anterior horn of the spinal cord at levels C1-C6, and the sternocleidomastoid muscle motoneurons were found at levels C1-C3. The click-evoked potentials recorded in this study reflect responses of the spinal nucleus of accessory nerves through the vestibulospinal tract to click stimulation. The responses have the same characteristics as vestibular-evoked myogenic potentials that can be recorded using surface electrodes over the sternocleidomastoid muscles of humans.     

Tongue Base Reduction with Temperature-controlled Radiofrequency Volumetric Tissue Reduction for Treatment of Obstructive Sleep Apnea Syndrome

In recent years a considerable effort has been made to establish the use of different surgical techniques for the treatment of obstructive sleep apnea syndrome (OSAS). Nevertheless, treatment of hypopharyngeal obstruction due to tongue base hypertrophy remains in many ways an unsolved problem. The aim of this study was to evaluate the safety and efficacy of tongue base reduction with temperature-controlled radiofrequency volumetric tissue reduction in the treatment of OSAS. Twenty patients with OSAS and tongue base hypertrophy were treated with radiofrequency tissue ablation. An intensified treatment protocol was used, delivering 2,800 J per treatment session under local anesthesia. Two nights of polysomnography testing were performed before and after treatment. Daytime sleepiness, snoring and postoperative morbidity were assessed using questionnaires. Mean respiratory disturbance index (RDI) was reduced from 32.1 to 24.9/h after a mean of 3.4 treatment sessions. Six patients (33%) were cured after the procedure (reduction in RDI of &#83 50% and a postoperative RDI of <15/h) and ten (55%) showed an improvement of >20% in their RDI. Daytime sleepiness and snoring improved significantly. Peri- and postoperative morbidity was low; one severe complication occurred (tongue base abscess). We were able to achieve similar cure and responder rates to those reported in a recently published pilot study but with a reduced number of treatment sessions. We believe that this technique may improve patient acceptance and have beneficial cost implications.     

Cochlear Function in Ears with Immunomediated Inner Ear Disorder

The aim of the present study was to evaluate the performance of ears with inner ear disorder, responsive to immunosuppressive drugs, in advanced tests designed to assess primary cochlear functions (temporal integration, frequency selectivity, cochlear mechanics). The results of this study suggest that immunomediated inner ear disease results, in the acute clinical stage, in the development of endolymphatic hydrops, which increases the stiffness of the vibrating structures within the inner ear and causes dysfunctions of the outer hair cells. Our patients presented with upsloping or flat sensorineural hearing loss, absence of evoked otoacoustic emissions and distortion-product otoacoustic evoked emissions and abnormal temporal integration, frequency selectivity and cochlear mechanics. Following immunosuppressive treatment, hydrops recovered, hearing subsequently returned to normal, the audiometric curve became flat at low-to-middle frequencies and primary cochlear function tended to normalize. This study seems to support the usefulness of testing primary cochlear functions in order to monitor the clinical course of immunomediated inner ear disorders.     

Bacterial Interference Between Pathogens in Otitis Media and Alpha-Haemolytic Streptococci Analysed in an In Vitro Model

Bacterial interference studied by means of agar methods has shown a decreased number of inhibitory alpha-haemolytic Streptococci among otitis-prone children. Additional information was gained regarding the interplay between alphahaemolytic Streptococci (AHS) and otitis media (OM) pathogens by comparing the bacterial interference in broth with the interference activity studied using agar overlay methods. We found that non-typeable Haemophilus influenzae (NTHI) and Moraxella catarrhalis are readily inhibited by AHS in broth. Streptococcus pneumoniae was more bacteriostatically inhibited. If two OM pathogens were inoculated simultaneously, an isolate of AHS with poor inhibitory activity was not able to inhibit the growth, in contrast to an isolate of AHS with good inhibitory activity. The initial amount of AHS inoculated with M. catarrhalis seemed to play a decisive role with respect to the inhibitory activity. M. catarrhalis developed reduced susceptibility against AHS both in vivo and in vitro . In vivo studies showed that children with secretory otitis media had fewer isolates of AHS in their nasopharynx with the ability to inhibit all the test pathogens than healthy children ( p < 0.001). Although the factor(s) responsible for the inhibitory activity have thus far not been defined, we could exclude low pH and nutrition depletion as the inhibitory mechanism of AHS with good inhibitory activity.